From owner-freebsd-net Mon Dec 2 6:49: 8 2002 Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 4067137B401 for ; Mon, 2 Dec 2002 06:49:07 -0800 (PST) Received: from mail.sandvine.com (sandvine.com [199.243.201.138]) by mx1.FreeBSD.org (Postfix) with ESMTP id AD58C43E9C for ; Mon, 2 Dec 2002 06:49:06 -0800 (PST) (envelope-from don@sandvine.com) Received: by mail.sandvine.com with Internet Mail Service (5.5.2653.19) id ; Mon, 2 Dec 2002 09:49:05 -0500 Message-ID: From: Don Bowman To: "'freebsd-net@freebsd.org'" Subject: SO_DONTROUTE, arp's, ipfw fwd, etc Date: Mon, 2 Dec 2002 09:49:03 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org I have a setup where I have a transparent proxy using ipfw fwd (to localhost). Data is sent to this device using a MAC rewrite so that packets arrive with my MAC, but the original source and destination IP. When I receive the SYN, i accept the connection, which causes an ARP to be emitted for the source address, and then the SYN/ACK. Now, I would like to have my default route not be on the 'data' interface which has the ipfw rule. It seems like this would work if: a) the MAC address for the source address (the router which sent me the packet) was entered into the ARP cache automatically when the SYN was received. b) I used SO_DONTROUTE in my proxy application. Does anybody have any comments on that? Is there a reason that learning ARP entries isn't done passively? I assume that since the receive interface is cached in the syncache, and then proxied through to the PCB, that the SO_DONTROUTE will cause the return packets to go back through that same interface? Is there a simpler way? --don (don@sandvine.com www.sandvine.com) To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message